Thursday, 23 December 2010

Open Access Article Originally Published: September 23, 2009 And Available from EV World

The hydrogen initiative is stalled. The hydrogen fuel cell cars work fine but no good solutions have been found to the problems of where to get the hydrogen, how to deliver it and how to store it. 95% of our hydrogen is made from natural gas, which is abundant on earth and already distributed at 1/3rd of the price of gasoline.

Three recent breakthroughs have made natural gas a very interesting fuel:

Ceramic fuel cells that can make electricity from natural gas at 60% efficiency.

A glut of cheap natural gas caused by new shale drilling/extraction techniques.

The fuel cell breakthrough is particularly important because it means a car can generate its own electricity more efficiently than a massive power plant! Big plants typically average 30% efficiency, so a 60% NG fuel cell hybrid is twice as efficient as an electric vehicle charged from the grid.

Fuel Cell in the Engine Bay

That means half as much fuel is consumed. Twice as efficient as an electric car is saying a lot because electric cars are already three times more efficient than conventional cars. This is because internal combustion engines are less than 30% efficient verses 90% for electric motors.

Natural gas fuel cell cars are thus about six times more efficient than today’s cars. Using 1/6th as much fuel means pollution is also 1/6th . But NG is inherently very clean. and has 30% lower carbon content and virtually no sulfur, mercury, volatiles, and Nox so pollution is way less than 1/6th.

Since NG fuel cells have a warm up time, the hybrid batteries must have enough capacity for all-electric operation until warm up is complete. After warm up, the fuel cell keeps the batteries charged and the batteries provide power for peak loads and acceleration and recapture energy on braking.

A Prius uses 16.8 kW for continuous 70 mph driving on a level road. The fuel cell must be able to supply this much power for steady driving. Natural gas is already distributed by pipeline to homes all over the US and UK, so home refueling is possible. Compressed Natural Gas (CNG) is already used to run five million vehicles worldwide. Pump prices for CNG are about one third of the price of gasoline in spite of the expensive ($350k), 3600 psi pumps and fittings currently used for delivery.

The pipeline cost of natural gas is only 1/4th of the cost of crude oil with the same energy content. If much simpler, 500 psi Adsorbed Natural Gas refueling is adopted, prices could be reduced even further.
Cost per mile for a NG fuel cell hybrid would currently be only 1/18th of present cars but could be reduced even further with low pressure ANG refueling! ANG fuel tanks contain activated carbon “sponges” that adsorb 160 times their own volume of natural gas. They can be made from Corn cobs , which have a network of nanoscale passageways that remain after carbonization. One gram of this material has as much adsorbing surface area as a football field.

When natural gas is adsorbed on a carbon surface it ceases to act like a gas. Dense storage at low pressure makes it possible to hide the much smaller tank inside the car's frame. Even if we kept the existing CNG high pressure storage, the tripled efficiency would allow fuel cylinders only 1/3rd as large as present CNG tanks.
So an NG fuel cell hybrid is a lot like a Chevy Volt with a fuel cell replacing the range extender (engine/generator) and a much smaller battery. Its battery only needs to be large enough to run the car during warm-up of the fuel cell, currently about 15 miles. The Chevy Volt's 40-mile battery is rumored to cost $5000, so the NG car's 15-mile battery would cost $3125 less. Incidentally, at these battery prices a 400-mile range pure electric car would need $50,000 worth of batteries!

Clearly, small batteries with range extenders are the way to go until we have a significant battery breakthrough. Pure electrics have other problems too: A 110v, 20A household plug can only supply 2.2 kW which means that, unless you add 220v service, 10 hours of home charging will only take you 10 x 2.2 x 4 mi/kW = 88 miles. Natural gas today is primarily a non-renewable, fossil fuel.

But people have already begun selling renewable gas into the pipeline. Landfills, manure piles and sewage plants that used to release significant amounts of methane into the atmosphere are now selling it as green gas. Biomass and garbage can also be gasified to add to the supply.

The energy balance of grass bio methane production is 50% better than annual crops now used. Though the US power grid uses significant hydro power and other renewables, CO2 emissions are still almost twice as much per kilowatt-hour as a 60% efficient NG fuel cell. In 2007 the US power grid emitted 605 grams/kWh.
A NG fuel cell emits only 327 grams. At 4mi/kWh that translates to about 151 grams per mile for a grid charged car verses 82 for the NG fuel cell car.

Someday the grid could be cleaned up so that electric cars charged from it are cleaner than NG fuel cell hybrids. EIA data makes it easy to track our progress towards this goal: In 1996 we emitted 627 grams of CO2 per kWh and by 2007 this was reduced to 605 grams.

That’s a 2-gram per year decrease. If we continue at that rate, it will take 139 years to equal what we can do now with a NG fuel cell. Recent years show even less progress. There was no improvement between 2006 and 2007. Plugging into the grid is, unfortunately, a bit like plugging into a lump of coal.

Infrastructure expansion also favors natural gas. Gas pipelines cost half as much to build as ugly overhead electric transmission lines of the same power capacity. Gas also has one fourth the transmission loss of electricity and much cheaper energy storage.

Depleted gas fields and salt caverns are already storing 4.1 Tcf of gas in the US. At 60% efficiency this could produce 1,970 gigawatt-hours of electricity. A very cheap battery! Fuel cell developers are in a race to commercialize suitable fuel cells. The first products using NG fuel cells are home CHP electricity generators that use their waste heat to make hot water. The fuel cells in these units produce only 2 kW but they can start up from an idle state in 5 or 6 minutes.

Scaling up to 15 kW and adapting to the tough environment of a car could take years. Another company is developing a fuel cell range extender that is fueled by methanol. Methanol has only half the energy density of gasoline but, because of the high efficiency, fuel tanks would still be smaller than current gasoline tanks. “Price at the pump” is the one thing that seems to get voters excited. Reducing fuel cost/mile by a factor of 18 with a fuel that is 97% from North America while using corncobs should generate some excitement. The hydrogen initiative should be immediately redirected to focus instead on a fuel that is plentifully available, transportable and storable.

Finally if the Governments of the US, UK Europe and the rest of the world wish to allow some kind of demarcation as its a transport fuel (and thus subject to some form of road pricing tax) then LPG is already available as both a transport fuel. It is also subject to the tax as well. LPG whilst a more complex molecule could still be developed as the fuel cell of choice by the motor industry.

Tuesday, 21 December 2010

Yes AD combined with CHP or even CHCP. What is all this acronym stuff eh?

AD Plant in UK The 'tanks' are where all that rotting organic stuff goes to

AD is Anaerobic Digestion, its the sort of process that happens in a sewage works where all that nasty stuff is broken down by 'good' bacteria. What is left is largely safe but has given off lots of methane gas and CO2, along with some other trace stuff. Anaerobic means 'without Oxygen'.

Now that Methane is what we need. Its almost the same as Natural Gas that you buy at home. So it can be 'cleaned up' and sent down pipes to the gas mains or it can run a gas fired electricity generator.

But rather than just generate electricity, we also need to look at how effective the burning of gas in an engine really is. When gas is burned in say a modified car engine to drive a shaft to turn a generator to produce electricity, there are loses. These loses affect the efficiency of turning the energy value of gas into electricity. It is disappointing to discover that only around 20-25% of the gas burnt produces the electricity. The rest is 'low grade' waste heat.

The Chinese have over 2 million of these AD-CHP Units

However, this so called 'low grade' heat to you and me living in a house is more than enough to give us central heating and hot water. It's also enough to run through a device called an 'absorbtion chiller' so we get chilled water to run an air conditioning system.

The good thing about using the 'waste' heat in this way is that we get a lot more use out of the energy (from the methane) gas. So 20-25% of the energy from the gas gives you the electrical power generation, but we can also get around 50-60% use from the Heating and Cooling. This jacks the efficiency of a CHCP system up to the 80-85% energy efficiency range. As you will agree its a lot better than 20-25%. So energy efficiency is a major benefit.

This is what a CHP unit looks like nothing to be scared of here?

If a CHP unit was to replace simple power generation then we can practically quadruple the benefits or useful energy. This is the basis of what is called 'Distributed Energy', rather than just focusing on electrical generation as our Utilities have done for a long time in the UK and US and the other nations they have 'sold' this daft idea to.

Now back to AD. As a 'consumer' (as we all are) we waste an awful lot of stuff in our everyday lives. As do the factories that produce 'processed foods' and our agricultural practices. Food we discard, grass cuttings, stuff we don't eat in a restaurant, unused oils and fats in cooking, effluents etc, in fact anything that will 'rot' down. Now imagine if the waste collection authority/company was to have an AD system to throw all this organic waste into.

Well they could then be in the power, heating and cooling business! Trouble is most of these organisations don't actually 'think outside of the box' like they all claim. If they did, rubbish collection would be really very profitable!

Furthermore "Waste to Energy" is an important concept. It's not the same as Waste to Electricity, that's only using 25% of the ENERGY potential (for electricity). The heat and cooling energy has to be utilised. It needs somewhere to go and someone to buy it as well. The distribution of heat and cooling energy is the 'hard bit'.

AD CHCP Flow Chart Concept

But that is the concept behind a coherent "waste to energy policy" that EVERY public authority or waste collection agency MUST adopt if their green credentials are to be believed. Otherwise its all just HOT AIR. (which is another story!!).

Saturday, 11 December 2010

Whilst certainly not the first its good to see London starting the long long route to phase out diesel buses. With plenty of good results in China, Australia and Germany these vehicles are a step in the right direction. However to replace all of London's buses is a multi-billion £ project likely to take 20 years or more. However their press release below is encouraging. Though as a practical interim step LPG should be considered

Zero-polluting hydrogen buses that emit only water were unveiled today in London, providing a boost to the Mayor's plans to improve the capital's air quality.

Trialled H Bus 2003-2007

The first of the buses, of a planned fleet of eight, will start operating on 18 December using the latest hydrogen fuel cell technology, emitting nothing but water vapour. The buses will form the only hydrogen bus fleet in the UK and the largest currently in Europe. These state-of-the-art vehicles were specifically designed for Transport for London using pioneering technology developed by ISE, Wrightbus and Ballard. All eight buses are expected to be phased into operation next year creating the UK's first zero-emission bus route.

The buses will join one of the cleanest, lowest polluting bus fleets in Europe which also includes 100 hybrid buses set to expand to 300 and from 2012 will be joined by the Mayor's New Bus for London, which will be 40% less polluting than a traditional diesel bus.

Boris Johnson, Mayor of London, said: "These buses are a marvel of hydrogen technology, emitting only water rather than belching out harmful pollutants. They will run through the most polluted part of the city, through two air pollution hotspots, helping to improve London's air quality. This is just another way that our city is harnessing pioneering low emission public transport to improve quality of life, whether the New Bus for London, electric vehicles or my public bike hire scheme."

David Brown, Managing Director for Surface Transport at TfL, said: "London faces many environmental challenges but we believe alternative fuels, such as hydrogen, will bring genuine long term benefits in tackling CO2 emissions. The arrival of these hydrogen hybrid fuel cell buses marks an exciting new chapter for London Buses as we embrace new technologies to further build on the excellent work we are doing to improve air quality for Londoners."

London has always been at the forefront in using and developing new technology, initially pioneering hydrogen buses in the UK when it took part in the Cleaner Urban Transport for Europe (CUTE) trial from December 2003 to January 2007. TfL operated three trial hydrogen buses on the route RV1, using findings from these trials and that of European partners to seek out these suppliers who have developed these next generation hydrogen fuel cell buses to operate in central London.

This next generation technology will be phased into service on route RV1 from Saturday 18 December whilst driver training takes place, with all the buses fully entering service in 2011.

The buses are jointly funded by TfL, the Department of Energy and Climate Change (DECC) and the European Union via the Clean Hydrogen in Cities (CHIC) project.

Fleet of London Buses

The London Hydrogen Partnership (LHP) launched an action plan earlier this year setting out ambitions to create a 'Hydrogen network' by 2012, to help accelerate the wider use of this zero-polluting, zero-carbon energy.

The LHP is working with London boroughs and private landowners on plans to deliver six refuelling sites to run hydrogen-powered vehicles in the capital over the next two years. It also aims to encourage a minimum of 150 hydrogen-powered vehicles on the road in London by 2012 including 15 hydrogen powered taxis

Friday, 10 December 2010

There is no argument about the direction of the future of motor vehicles. All electric, Hybrid, Hydrogen Fuel cells etc. They are all being developed. But.

What are we going to do with the 806,000,000 petrol and diesel vehicles already out there? I mean firstly not everybody can go and buy an alternative vehicle right now or even in the medium term. In addition manufacturers and the raw materials markets could not cope either. So whats the compromise?

In practice the transition to alternative powered vehicles might take between 30-50 years. This is based on how a 'new' concept can become accepted as the 'conventional wisdom'. This occurs in all sorts of industries, from transport to construction. Reinforced concrete took 40 years to gain a place along side steel and brick. The diesel car took over 30 years in the UK to become 'accepted'. In addition technological advances along the way are also required.

And let's not forget that the fight will be for dominance in the alternative energy cars, will it be Hydrogen Fuel Cell, All Electric, Hybrids or what? Remember VHS and BetaMax, then Blu Ray and HD. Which technology will win this race and what is the attrition rate to be? Who out there will be left owning some of the 'losers' technology without the means to use it?

Therefore an intermediate step towards 'cleaner' technologies and fuels is needed. Now that diesel vehicles have become almost 'standard' we have to look at the disadvantages of diesel as a fuel. Irrespective of the relatively low CO2 emission, diesel has many other unpleasant problems, such as soots or 'black carbon'.

These products of incomplete combustion are rather bad, in fact some are considered carcinogenic. They also explain why your engine oil gets so dirty so quickly. Diesel is a 'heavy fuel' with a very complex structure. During combustion many differing compounds are created. This is why diesels are less suited in urban environments such as city centres. Its also why the diesel taxi is now falling out of favour.

In Hong Kong for example there are no diesel taxis at all. Being a very densely populated area, diesel exhaust emissions are becoming problematic. Not just human health either. The Sulphur compounds can accelerate the erosion of buildings when combined with rain.

Therefore Autogas Network has decided that this transition fuel system should be built around LPG - Liquefied Petroleum Gas. LPG or Autogas is a mixture of Butane and Propane gases that have been lightly compressed to be stored in a compact fuel tank as a liquid. LPG has the added advantage that it is extremely clean burning with so little deposits from combustion that your engine oil will remain clean much longer (up to 70,000 miles is not unknown).

Not only is it much cleaner than diesel and so ideal for high mileage taxis in urban locations, it emits less than 99.9% less soot than a diesel cab. Furthermore the infrastructure is already in place. In Europe there are over 8 million LPG dual fuel cars with over 32,000 filling stations. In the UK alone there are 1,440 filling stations. So its not like the future or cars; where we need additional filling points and infrastructure.

LPG or Autogas is the ideal intermediate fuel, the ideal compromise for cleaner cheaper motoring for all those existing petrol vehicles out there or still to be built. Let's not forget that the current motor manufacturers are still making brand new cars and have spent a huge amount of money in setting up production lines. These cannot just be switched off and electric cars produced - it will take years.

Wednesday, 8 December 2010

Construction of a fuel cell with enough capacity to power 2,800 homes has begun on the UC San Diego campus as part of a renewable energy project with the city of San Diego and BioFuels Energy to turn waste methane gas from the Point Loma Wastewater Treatment Plant directly into electricity without combustion.

UC San Diego's 2.8-megawatt fuel cell

When completed in late 2011, the 2.8-megawatt fuel cell will be the largest on any college campus, providing about 8 percent of UC San Diego’s total energy needs. The $19 million project requires no university funding: The project is eligible for $7.65 million in California Self Generation Program incentives; BioFuels Energy will provide the remaining $11.35 million in private investment, loans and investment tax credits.

“Our campus currently generates 85 percent of its own power. With this new fuel cell and the near-doubling of our photovoltaic solar capacity in 2011, our campus will be able to meet as much as 95 percent of our annual electricity needs,” said Gary C. Matthews, vice chancellor of resource management and planning. “The fact that we’ve been able to significantly increase our renewable-energy capacity in very challenging economic times with an innovative public-private partnership is as much a financial feat as it is an engineering accomplishment.”

As part of a 10-year agreement, UC San Diego will buy the electricity produced by the fuel cell from BioFuels Energy at competitive rates. The university’s fuel cell also offers the potential benefits of cogeneration, or combined heat and power, in which waste heat can be tapped as a secondary power source, raising the overall net efficiency of the fuel cell to about 60 percent, compared with about 33 percent for coal- and oil-fired power plants.

About 85 percent of the university’s energy needs are provided by its low-emission 30-megawatt natural-gas-fired cogeneration plant, which operates at 66 percent overall net efficiency. It is also called a combined heat and power plant because it generates electricity to run lights and equipment and also captures the plant’s waste heat to produce steam for heating, ventilation and air conditioning for much of the 12.5 million gross square feet of campus buildings. Waste heat from the plant also is used as a power source for a water chiller that fills a 3.8-million-gallon storage tank at night with cold water, which allows the university to reduce its peak daytime energy requirements by about 14 percent.

The fuel cell and its ancillary equipment will occupy a space about the size of a tennis court. It will form the centerpiece of UC San Diego’s Energy Innovation Park on the east side of the main campus, which includes:

• High efficiency, 5.75-kilowatt sun-tracking concentrating photovoltaic array made by Concentrix Solar.
• A compressed natural gas (CNG) fueling station for 13 CNG service vehicles, including two delivery trucks and two street sweepers, three sedans, three pick-up trucks and three buses. Vehicle emissions are lower with natural gas fuel than with gasoline because CNG-fueled vehicles emit 10 percent less carbon dioxide compared to diesel and 30-40 percent less than equivalent gasoline-fueled vehicles.
• A chiller plant that efficiently produces the cold water required to cool the nearby Moores UCSD Cancer Center and Shiley Eye Center.
In the future the energy park will have an array of additional technologies:
• An electric-vehicle charging station.
• A second chiller plant with 300 kilowatts of cooling capacity that will be powered by the fuel cell’s waste heat to cool the Cancer Center, Shiley Eye Center and other UC San Diego medical treatment, research and office buildings nearby.
• An energy-storage system that will stockpile four hours’ output of electricity from the fuel cell every night during off-peak hours and release the electricity to the campus energy grid during peak-demand hours in the afternoon.

The planned energy-storage system is eligible for an additional $3.4 million in Self Generation Program incentives and could reduce UC San Diego’s peak energy demand by 6 percent.

“The university’s increasingly sophisticated microgrid will integrate all the campus’

production, consumption and stored power and cooling water into one of the most sophisticated energy-management systems anywhere,” said John Dilliott, energy and utilities manager for the campus. “We will soon be able to factor in the variable cost of imported electricity and optimize the production and consumption of electricity in our entire system with a high degree of cost and energy efficiency.”

The city of San Diego will make money by selling the Point Loma Wastewater Treatment Plant’s biogas, which is purified on site and injected into an existing gas pipeline that will supply three fuel cells being constructed, one at UC San Diego and two at city of San Diego sites. “This project and the uniqueness of the concept is anticipated to pave the way for similar future applications,” said Frank Mazanec, managing director of Encinitas, Calif.-based BioFuels Energy.

The three fuel cells are made by Danbury, Conn.-based FuelCell Energy, Inc. and use an electrochemical process to combine the methane fuel with oxygen in ambient air to produce electricity directly. Carbon dioxide and water vapor are also produced, but no nitrate or particulate pollutants are produced because there is no combustion.

The so-called directed biogas project is the first time that a FuelCell Energy power plant will be fueled by renewable biogas generated at a distant location.

The fuel cell being built at UC San Diego is one of the largest fuel cells in the nation to use directed biogas from a wastewater treatment plant,” said Kenneth J. Frisbie, also managing director at BioFuels Energy. "No university has a fuel cell this big."

Friday, 3 December 2010

(Source PhysOrg.com and DigInfo TV) -- A joint project by universities in Algeria and Japan is planning to turn the Sahara desert, the largest desert in the world, into a breeding ground for solar power plants that could supply half the world’s electrical energy requirements by 2050

The Sahara Solar Breeder Project aims to begin by building a silicon manufacturing plant in the desert to transform silica in the sand into silicon of sufficiently high quality for use in solar panels. Solar power plants will be constructed using the solar panels, and some of the electricity generated will supply the energy needed to build more silicon plants to produce more solar panels, to produce more electricity...

Leader of the Japanese team, Hideomi Koinuma from the University of Tokyo, said while no one has tried to use desert sand as a source of high-quality silicon before, it is the obvious choice and will be of high enough quality.

The energy generated by the solar power plants will be distributed as direct current via high-temperature superconductors, a process that Koinuma said will be more efficient than using alternating current. He envisages a large network of supercooled high-voltage direct current grids capable of transporting the expected 100 GW of electricity at least 500 kilometers. Even if the grid needs to be cooled with liquid nitrogen, Koinuma said it could still be cost-competitive. (High-temperature superconductors operate at about -240°C.)

The Sahara Solar Breeder Project (dubbed the Super Apollo Project by Koinuma) is being developed as part of the International Research Project on Global Issues by the Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). The team expects to have to overcome many problems, including frequent sandstorms, the need to use liquid nitrogen to cool cables and to bury them in the sand to minimize fluctuations in temperature, and so on.
The initial aims of the research will be focused on tackling the expected challenges and demonstrating the project’s viability. Training engineers and scientists from Africa in the entire research and development process is also a goal of the project.

Another project aiming to harness solar power in the Sahara was launched last year. The Desertec Foundation aims to supply 15 percent of Europe’s electricity requirements by 2050 using high-voltage direct current transmission lines without superconductors The Destertec Project will also use mainly Solar Thermal Technology and little Solar Photo-Voltaic. This is in addition to providing desalinization plants and domestic electricity to all the North African nations.

China' transport strategy gains an important boost with this achievement. Now as long as the electrical power is generated with clean technology then this is a great step forward.

The Xinhua News Agency said it was the fastest speed recorded by an unmodified conventional commercial train. Other types of trains in other countries have traveled faster.

This sleek conventional train powered by electricity hit over 302 mph

A specially modified French TGV train reached 357.2 mph (574.8 kph) during a 2007 test, while a Japanese magnetically levitated train sped to 361 mph (581 kph) in 2003.

State television footage showed the sleek white train whipping past green farm fields in eastern China. It reached the top speed on a segment of the 824-mile (1,318-kilometer) -long line between Zaozhuang city in Shandong province and Bengbu city in Anhui province, Xinhua said.

The line is due to open in 2012 and will halve the current travel time between the capital Beijing and Shanghai to five hours.

The project costs $32.5 billion and is part of a massive government effort to link many of China's cities by high-speed rail and reduce overcrowding on heavily used lines.

China already has the world's longest high-speed rail network, and it plans to cover 8,125 miles (13,000 kilometers) by 2012 and 10,000 miles (16,000 kilometers) by 2020.

The drive to develop high-speed rail technology rivals China's space program in terms of national pride and importance. Railway officials say they want to reach speeds over 500 kph (312 mph).

Wednesday, 1 December 2010

The process, using a unique integrated catalytic process, could open the door to a chemical industry based on renewable biomass feedstock.

Dwindling petroleum resources combined with economic, environmental and political concerns about the petroleum-based economy in which we live makes it imperative to develop new processes for the production of renewable fuel and chemicals.

The research, led by the University of Massachusetts-Amherst (UMASS) in collaboration with experts at Southeast University, Nanjing in China and Nottingham, and published in the journal Science, demonstrates how cheap renewable pyrolysis oil, bio-oils produced from biomass, can be upgraded into high commodity chemicals such as mono-alcohols, diols, light olefins and aromatic hydrocarbons — which are used in the production of plastics.

Because of their oxygen content these bio-oils have not been of high enough quality to use in the production of synthetic fuels so far. Now the team of scientists have converted the bio-oils into 11 different biomass-derived feedstocks using a de-oxygenation process which makes them more compatible with current fuels and chemical crude oil refinery settings.

Aimaro Sanna, from the Department of Chemical and Environmental Engineering, said:

“Overall, this is a very promising and flexible catalytic process that would sensibly decrease the economical disadvantage of biomass compared with fossil fuels and would make possible the conversion of biomass on an industrial scale.”

This new catalytic process is flexible enough to produce different targeted distribution of organics to suit different existing petrochemical products in function of the different market conditions — for instance gasoline additive or feedstock for the chemicals industries.

Currently, Aimaro Sanna is a research associate at the National Centre for Carbon Capture and Storage (NCCCS) based in the University of Nottingham’s Division of Energy and Sustainability. The Centre addresses issues of global importance in the area of sustainable and affordable energy technologies.
He said: “My contribution to this work came out of an intense six month research collaboration at the Catalysis Bioenergy Centre at UMASS led by Professor George Huber working on the bio-oil hydrotreating. The goal of the project was to add hydrogen to the biomass derived molecules by reducing thermally unstable functionalities to more stable alcohols and by controlled cleavage of C-C and C-O bonds without consume high amount of hydrogen required in a typical full hydrotreating process.”

Future advances in the field of metal and zeolite catalysts, combined with reaction engineering, will lead to the design of even more efficient and economical processes to convert biomass resources to renewable chemical industry feedstocks.

The Nottingham research group lead by Dr. John Andresen is also proposing an innovative multi-steps catalytic process able to convert biomass into bio-oil by catalytic pyrolysis.

Despite the fact that the original biomass contains undesirable high oxygen contents, the catalytic pyrolysis under investigation is able to sensibly decrease its oxygen content. This would be beneficial to the further upgrading of the bio-oil by the novel process developed at UMASS due to a low amount of hydrogen that would be required in presence of low oxygen level in the starting bio-oil.

The University of Nottingham has a broad research portfolio but has also identified and badged 13 research priority groups, in which a concentration of expertise, collaboration and resources create significant critical mass. Key research areas at Nottingham include energy, drug discovery, global food security, biomedical imaging, advanced manufacturing, integrating global society, operations in a digital world, and science, technology & society.

Through these groups, Nottingham researchers will continue to make a major impact on global challenges.

Supplying Electricity (or more accurately supplying ENERGY) is in the process of metamorphosis because people want to know what is the most sensible and efficient way to utilize all types of energy sources and needs. German researchers at Fraunhofer put the most common ideas for heating under the microscope and come up with findings that may not please the larger utility companies.

6 Cooling Towers shown 3 either side of the main generation building allow the rejection of around 60% of the energy released by this coal fired station to be sent into the atmosphere. The steam rising from this wasteful practice is often confused as smoke from the burning of coal.

This work from the respected Fraunhofer Institute in Germany is starting to ask some radical questions about the conventional thinking in centralized power generation. Looking at decentralization and combining power with heat and cooling loads can make fuel burning efficiencies as high as 80% and compares much better than the wasteful cooling tower designs which let 60% of the fuel energy be 'wasted' to the atmosphere. John Burke SEE, 1st December 2010.

Supplying energy is in the process of metamorphosis because people want to know what is the most intelligent and efficient way to utilize all types of energy carriers. German researchers at Fraunhofer put the most common ideas for heating under the microscope and come up with major potential.

Carsten Beier from the Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT in Oberhausen, Germany does not believe that “anyone would burn a 50-dollar bill just to keep warm. It’s obvious that it simply is too valuable for that.” But, in contrast to dollar bills, most energy carriers are all too frequently burned for less than they are worth. Take wood, for example. Beier and his colleagues have analyzed the efficiency of heat supply systems and he explains that “wood is a high-quality fuel that can be compared to natural gas. With adequate technologies we could utilize it for power generation. As a fuel, there‘s a lot more in wood that we are taking advantage of at the moment.”

Beyond this, the researchers at the Fraunhofer Institute for Environmental, Safety and Energy Technology have come up with a model for comparing various systems and technologies in heat supply ranging from heating boilers for single-family dwellings right down to district heating networks for whole cities. They apply exergy as a criterion of analysis which is a thermodynamic parameter defined by the quantity and quality of an energy. In contrast to the CO2 balance sheet and primary energy consumption, the exergy analysis indicates whether we are sufficiently taking advantage of the potential lying dormant in the energies we use. Carsten Beier has come to the conclusion that “if we used fuels such as natural gas or wood for power generation and only use the waste heat for heating, we would be able to save large quantities of primary energy and avoid generating CO2 emissions.”

Cogeneration plants are taking advantage of these potentials. While large-scale power plants lose an average of 60 percent of the energy as waste heat through the cooling tower, cogeneration plants use this flow of heat for heating purposes, which means that they achieve overall efficiency of more than 80 percent.

The researchers distinguished four categories of heat generation in their analyses: burning, cogeneration and using heat pumps or waste heat from industrial processes.

Comparing these categories, using waste heat was particularly good in connection with heat networks. That said, it also became apparent that the way drinking/washing water was heated was a key factor in exergy efficiency. Beier reveals that ”even heating a room with waste heat has a poor overall exergy balance sheet if the service water for the household is electrically heated.”

Researchers derived one basic recommendation from their comparison of systems and technologies. Beier demands

”we should take advantage of all sources of heat whose temperature level corresponds to our heating requirements.”

And we could take advantage of the fact that there are a whole series of applications where heat is needed at different temperature levels.

Beier explains how.

”Any type of cascade is very efficient. For instance, if you use fuel for power generation first, then the waste heat for water heating and finally the remaining heat for space heating.”

CHP utilises the differing forms of energy from the generation of elctricity

He confesses that there might be discussions on the economic efficiency of these scenarios, especially because the initial investments are rather high. “But, on the other hand, it is essential to restructure our energy system quickly and an exergy analysis is an excellent tool for identifying how power supply should be designed in future.“

Friday, 19 November 2010

Stadium to Generate it's Own Clean Electricity and Save $60 Million in Energy Costs
$30 million Investment in Wind Turbines, Solar Panels and Dual-Fuel Co-gen Plant To be Installed. The implication here is that the 7.6 megawatt on site CHP will underpin all energy needs on site and provide a surplus to the local area via selling back this energy to the power grid company.

SEECOMMENT: This is a great example of a project that should be replicated on all large scale construction projects around the globe. With large scale embedded energy production, comes the realization that decentralized power systems offer better power security. They also obviate the need for large scale generally inefficient remotely located power stations. Lets see what the UK's 2012 Olympic development has to offer in these realms of energy generation on this scale. The World Games stadium in Taiwan which opened last year was self powered albeit with solar panels.

Artists impression of finished stadium with VAWT around 'rim'

The Philadelphia Eagles today announced a plan to power Lincoln Financial Field with a combination of onsite wind, solar and dual-fuel generated electricity, making it the world’s first major sports stadium to convert to self-generated renewable energy.

The Eagles have contracted with an Orlando FL, renewable energy and energy conservation company, to install approximately 80, 20-foot spiral-shaped vertical axis wind turbines [VAWT] on the top rim of the stadium, affix 2,500 solar panels on the stadium’s façade, build a 7.6 megawatt onsite dual-fuel co-generation [CHP] plant and implement sophisticated monitoring and switching technology to operate the system.

Over the next year, they will invest in excess of $30 million to build out the system, with a completion goal of September 2011. A private provider will maintain and operate the stadium’s power system for the next 20 years at a fixed percent annual price increase in electricity, saving the Eagles an estimated $60 million in energy costs.

The Eagles estimate that over the 20-year horizon, the on-site energy sources at Lincoln Financial Field will provide 1.039 billion kilowatt hours of electricity — more than enough to supply the stadium’s power needs — enabling an estimated four megawatts of excess energy off-peak to be sold back to the local electric grid.

“The Philadelphia Eagles are proud to take this vital step towards energy independence from fossil fuels by powering Lincoln Financial Field with wind, solar and dual-fuel energy sources,” said team owner and chief executive officer, Jeffrey Lurie. “This commitment builds upon our comprehensive environmental sustainability program, which includes energy and water conservation, waste reduction, recycling, composting, toxic chemical avoidance and reforestation. It underscores our strong belief that environmentally sensitive policies are consistent with sound business practices.”

Added Eagles owner Christina Lurie, “We believe the iconic stature and universal appeal of professional sports can become a powerful, visible, motivating example of how renewable energy sources can replace fossil fuels and create a cleaner, sustainable environment for people everywhere.”

Against a backdrop of trees symbolizing the Eagles’ commitment to reforestation, the Luries invited special guests to join them in signing the Go Green! Team’s Declaration of Energy Independence, which “seeks to create a better living environment by reducing the world’s dependence on fossil fuels.”

The greening of Lincoln Financial Field is a significant step by a major sports franchise to achieve that goal. The energy to be generated by on-site renewable sources is comparable to the annual electricity usage of 26,000 homes. Engineers estimate that converting the stadium to renewable energy will eliminate CO2 emissions equivalent to 500,000 barrels of oil or 24 million gallons of gasoline consumed annually. That equates to removing the carbon emissions of 41,000 cars each year.

“The Eagles’ plan for Lincoln Financial Field represents one of the most extensive renewable energy commitments by any major facility”. “The energy plan will utilize the most technologically advanced wind turbines and solar panels. With this installation, we anticipate that many businesses will see the benefits of renewable energy and be inspired to emulate the Eagles’ bold leadership.”

Beyond the substantial environmental advantages, the Eagles’ renewable energy plan will create hundreds of jobs for the Philadelphia area. They anticipate directly employing 200 local people during the year-long design and installation phase. One-quarter of these jobs will be permanently maintained over the 20-year operational horizon. In addition, the project will generate approximately 600 indirect jobs in the surrounding region as a result of their commitment to utilize local contractors, vendors and suppliers, as available.

Philadelphia Mayor Michael Nutter stated, “The Philadelphia Eagles have been great corporate citizens for many years, most specifically working with disadvantaged youth throughout the City. But we also know the Eagles to be green; they don’t just wear green, they sincerely believe in the concept of responsible environmental stewardship. We appreciate their commitment to an issue that is at the core of the City’s Greenworks Philadelphia Plan, to become the Greenest City in America. Today’s announcement will help reduce the City’s carbon footprint, create hundreds of much needed green jobs and put our City on the world stage. This type of forward thinking will serve as an excellent example to every organization that wants to play a role in strengthening our local economy while helping the environment.”

NFL Commissioner Roger Goodell stated, “With this ground-breaking initiative, the Eagles are taking another significant step forward in their commitment to environmental responsibility and to their community. The work of the Eagles’ Go Green! initiative in raising environmental awareness and implementing green programs is a tribute to the leadership of the organization. The NFL is proud to support the Eagles and Christina and Jeffrey Lurie as they set the right example for all of sports.”

About The Philadelphia Eagles

The Philadelphia Eagles are members of the NFC East division of the National Football League (NFL). Under its current leadership, the team has become known as one of the most aggressive as well as progressive organizations in professional sports. Off the field the Eagles are recognized as a leader in community outreach having founded the Eagles Youth Partnership, one of professional sports’ most innovative charitable foundations, and Go Green, the team’s comprehensive environmental initiative. For more information visit the Eagles website at www.PhiladelphiaEagles.com.

Wednesday, 10 November 2010

First postulated in 1931 by Isidoro Cabanyes who discussed it in the magazine 'La energía eléctrica', this concept uses several key effects to work; the chimney effect, greenhouse warming and low velocity wind turbines.

The sun's radiation is used to heat a large body of air under an expansive collector zone (green houses in this case),

Solar Up Draught Tower Principles

which is then forced by the laws of physics (hot air rises) to move as a hot wind through large turbines to generate electricity. A Solar Tower power station will create the conditions to cause hot wind to flow continuously through 32 x 6.25MW pressure staged turbines to generate electricity.

One of the major advantages of a Solar Tower over other renewable and traditional coal & nuclear energy producers is a Solar Tower does not use any water in the energy production process.
A US Department of Energy report 'Reducing water consumption of concentrated solar powerelectrictity generation', states coal, nuclear and heliostat CSP technology (power tower) utilize approximatley 500 gallons of water per MWh of power produced.
The Solar Tower project earmarked for Arizona will abate the approximate usage of 528 million gallons of potable water (drinking water) per annum.'

Solar Up Draught Tower with Thermal Storage

Artists Impression of the Finished 'Power Station'

When using green houses crops can be grown and/or some heat energy can be retained overnight using water filled tubes as can be seen in this schematic below. This allow for the generation of power over a 24 hour period.

Monday, 1 November 2010

Good news from California and for Solar Thermal Plant (as opposed to solar PV panels). These reflectors concentrate light onto tubes filled with a heat transfer medium. This in turn is stored in insulated tanks and used over a 24hour period to power turbines to generate electricity - thus power at night!. Big in Spain and perfected by the Germans, this is an international project. See below from their press release.

Solar Trust of America, LLC today announced that its project development subsidiary, Solar Millennium, LLC, has secured a Record of Decision (ROD) from the Department of Interior’s Bureau of Land Management (BLM) approving the Blythe Solar Power Plant’s Right of Way Grant. The ROD is the final regulatory milestone in the federal permitting process and it paves the way for Solar Millennium, LLC to build and operate its Blythe Solar Power Project, which will be the largest solar power facility in the world.

Located in Riverside County, California, the Blythe solar power facility, will be the first parabolic trough solar facility approved on U.S. public land. It will consist of four 250 MW plants that together will deliver 1,000 MW of nominal generating capacity, or enough electricity to annually power more than 300,000 single-family homes. Upon completion the Blythe facility will increase the solar electricity production capacity of the U.S. by more than double, according to statistics from the U.S. Department of Energy.

Thursday, 28 October 2010

A new company, Kepler Energy Limited, has been formed to develop a tidal turbine which has the potential to harness tidal energy more efficiently and cheaply, using a device which is simpler, more robust and more scaleable than current designs.

The new design of tidal turbine. Image courtesy of University of Oxford

The turbine is the result of research in Oxford University's Department of Engineering Science by Professor Guy Houlsby, Professor of Civil Engineering, Dr. Malcolm McCulloch, head of the electrical power group, and Professor Martin Oldfield, Emeritus Professor of the thermofluids laboratory.

Kepler Energy Limited will design, test and develop a horizontal axis water turbine intended to intersect the largest possible area of current. The rota is cylindrical and rolls around its axis, thereby catching the current. The researchers received £50,000 in funding from the Oxford University Challenge Seed fund, managed by Isis Innovation, to build a 0.5 metre diameter prototype demonstrating the benefits of the design. A full-scale device would measure up to 10 metres in diameter, and a series of turbines can be chained together across a tidal channel.

UK waters are estimated to offer 10 per cent of the global extractable tidal resource. Tidal currents are sub-surface, so tidal turbines have minimum visual impact, unlike wind farms or estuary barrage schemes.
Tom Hockaday, managing director at Isis Innovation said: 'This is the latest in a number of spin-outs from the Department of Engineering Science. Isis is fortunate to work with such an entrepreneurial department, particularly on technologies which have the potential to make a big impact on our energy supply.'

Tuesday, 26 October 2010

Small is beautiful in hydroelectric power plant design, and good for the environment

In the shaft power plant design developed at the Oskar von Miller Institute of the Technische Universitaet Muenchen, water drops vertically into a concrete housing dug into the river bed, turns the turbine of a submersible generator, and returns to the river below the dam. This photo shows an experimental model of a shaft power plant -- without the water. Credit: TU Muenchen

Hydroelectric power is the oldest and the "greenest" source of renewable energy. In Germany, the potential would appear to be completely exploited, while large-scale projects in developing countries are eliciting strong criticism due to their major impact on the environment. Researchers at Technische Universitaet Muenchen (TUM) have developed a small-scale hydroelectric power plant that solves a number of problems at the same time: The construction is so simple, and thereby cost-efficient, that the power generation system is capable of operating profitably in connection with even modest dam heights. Moreover, the system is concealed in a shaft, minimizing the impact on the landscape and waterways. There are thousands of locations in Europe where such power plants would be viable, in addition to regions throughout the world where hydroelectric power remains an untapped resource.

In Germany, hydroelectric power accounts for some three percent of the electricity consumed – a long-standing figure that was not expected to change in any significant way. After all, the good locations for hydroelectricpower plants have long since been developed. In a number of newly industrialized nations, huge dams are being discussed that would flood settled landscapes and destroy ecosystems. In many underdeveloped countries, the funds and engineering know-how that would be necessary to bring hydroelectric power on line are not available.

Smaller power stations entail considerable financial input and are also not without negative environmental impact. Until now, the use of hydroelectric power in connection with a relatively low dam height meant that part of the water had to be guided past the dam by way of a so-called bay-type power plant – a design with inherent disadvantages:

The large size of the plant, which includes concrete construction for the diversion of water and a power house, involves high construction costs and destruction of natural riverside landscapes.

Each plant is a custom-designed, one-off project. In order to achieve the optimal flow conditions at the power plant, the construction must be planned individually according to the dam height and the surrounding topography. How can an even flow of water to the turbines be achieved? How will the water be guided away from the turbines in its further course?

Fish-passage facilities need to be provided to help fish bypass the power station. In many instances, their downstream passage does not succeed as the current forces them in the direction of the power plant. Larger fish are pressed against the rakes protecting the intake of the power plant, while smaller fish can be injured by the turbine.

A solution to all of these problems has now been demonstrated, in the small-scale hydroelectric power plant developed as a model by a team headed by Prof. Peter Rutschmann and Dipl.-Ing. Albert Sepp at the Oskar von Miller-Institut, the TUM research institution for hydraulic and water resources engineering. Their approach incurs very little impact on the landscape. Only a small transformer station is visible on the banks of the river. In place of a large power station building on the riverside, a shaft dug into the riverbed in front of the dam conceals most of the power generation system. The water flows into a box-shaped construction, drives the turbine, and is guided back into the river underneath the dam. This solution has become practical due to the fact that several manufacturers have developed generators that are capable of underwater operation – thereby dispensing with the need for a riverbank power house.

TU Muenchen civil engineer Albert Sepp (left) and Professor Peter Rutschmann are co-developers of the shaft power plant design. The power plant, most of which lies concealed below the riverbed, is designed to let fish pass along with the water. Credit: TU Muenchen

The TUM researchers still had additional problems to solve: how to prevent undesirable vortex formation where water suddenly flows downward; and how to best protect the fish. Rutschmann and Sepp solved two problems with a single solution – by providing a gate in the dam above the power plant shaft. In this way, enough water flows through to enable fish to pass. At the same time, the flow inhibits vortex formation that would reduce the plant's efficiency and increase wear and tear on the turbine.

The core of the concept is not optimizing efficiency, however, but optimizing cost: Standardized pre-fabricated modules should make it possible to order a "power plant kit" just like ordering from a catalog. "We assume that the costs are between 30 and 50 percent lower by comparison with a bay-type hydropower plant," Peter Rutschmann says. The shaft power plant is capable of operating economically given a low "head" of water of only one to two meters, while a bay-type power plant requires at least twice this head of water. Series production could offer an additional advantage: In the case of wider bodies of water, several shafts could be dug next to each other – also at different points in time, as determined by demand and available financing.

Investors can now consider locations for the utilization of hydropower that had hardly been interesting before. This potential has gained special significance in light of the EU Water Framework Directive. The directive stipulates that fish obstacles are to be removed even in smaller rivers. In Bavaria alone, there are several thousand existing transverse structures, such as weirs, that will have to be converted, many of which also meet the prerequisites for shaft power plants. Construction of thousands of fish ladders would not only cost billions but would also load the atmosphere with tons of climate-altering greenhouse gas emissions. If in the process shaft power plants with fish gates and additional upstream fish ladders were installed, investors could shoulder the costs and ensure the generation of climate-friendly energy over the long term – providing enough power for smaller communities from small, neighborhood hydroelectric plants.

Shaft power plants could also play a significant role in developing countries. "Major portions of the world's population have no access to electricity at all," Rutschmann notes. "Distributed, local power generation by lower-cost, easy-to-operate, low-maintenance power plants is the only solution. For cases in which turbines are not financially feasible, Rutschmann has already come up with an alternative: "It would be possible to use a cheap submersible pump and run it in reverse – something that also works in our power plant."

Thursday, 14 October 2010

From Arizona University comes a very promising break-through in utilising heat energy. The heat wasted in electrical generation is monstrous, typically 2kW of heat produced from every 1kW of electricity generated. Traditionally this is just dissipated in the cooling towers to the atmosphere.

Benzene Rings in Theoretical Device

But if this waste energy can be harnessed and turned into more electricity then this 'wasted' energy can be properly harvested. Report below.

With rapid industrialization, the world has seen the development of a number of items or units, which generate heat. Until now this heat has often been treated as a waste, making people wonder if this enormous heat being generated can be transformed into a source of electric power. Now, with the physicists at the University of Arizona finding new ways to harvest energy through heat, this dream is actually going to become a reality.

University of Arizona Research Team: The research team is headed by Charles Staffor. He is the associate professor of physics, and he along with his team worked on harvesting energy from waste. The team’s findings were published in the September 2010 issue of the scientific journal, ACS Nano.

Justin Bergfield who is an author and a doctoral candidate in the UA College of Optical Sciences shares his opinion, “Thermoelectricity can convert heat directly into electric energy in a device with no moving parts. Our colleagues in the field tell us that they are confident that the device we have designed on the computer can be built with the characteristics that we see in our simulations.”

Advantages: Elimination of Ozone Depleting materials: Using the waste heat as a form of electric power has multiple advantages. Whereas on one hand, using the theoretical model of molecular thermoelectric helps in increasing the efficiency of cars, power plants factories and solar panels, on the other hand efficient thermoelectric materials make ozone-depleting chlorofluorocarbons, or CFCs, outdated.

More Efficient Design: The head of the research team Charles Stafford is hopeful about positive results because he expects that the thermoelectric voltage using their design will be 100 times more than what others have achieved. If the design of the team, which they have made on a computer does work, it will be a dream come true for all those engineers, who wanted to catch and make use of energy lost through waste but do not have the required efficient and economical devices to do so.

No need for Mechanics: The heat-conversion device invented by Bergfield and Stafford do not require any kind of machines or ozone-depleting chemicals, as was the case with refrigerators and steam turbines, which were earlier used to convert waste into electric energy. Now, the same work is done by sandwiching a rubber-like polymer between two metals, which acts like an electrode. The thermoelectric devices are self-contained, need no moving parts and are easy to manufacture and maintain.

Utilisation Of Waste Energy: Energy is harvested in many ways using the car and factory waste. Car and factory waste can be used for generating electricity by coating exhaust pipes with a thin material, which is a millionth time of an inch. Physicists also take advantage of the law of quantum physics, which though not used often enough, gives great results when it comes to generating power from the waste.

Advantage Over Solar Energy: Molecular thermoelectric devices may help in harvesting energy from the sun and reduce the dependence on photovoltic (PV) cells, whose efficiency in harvesting solar energy is going down. SEE COMMENT: Thus solar thermal collectors, which are far cheaper than PV could eventually be utilised for direct electrical generation in the home or commercially.

How It Works

Though having worked on the molecule and thinking about using them for a thermoelectric device, Bergfield and Stafford had not found anything special till an undergraduate discovered that these molecules had special features. A large number of molecules were then sandwiched between electrodes and exposed to a stimulated heat source. The flow of electrons along the molecule was split in two once it encounters a benzene ring, with one flow of electrons following along each arm of the ring.

The benzene ring circuit was designed in such a way that the electron travels longer distance round the rings in one path, which causes the two electrons to be out of phase when they reach the other side of the benzene ring. The waves cancel out each-other on meeting. The interruption caused in the flow of electric charge due to varied temperature builds up voltage between electrodes.

The effects seen on molecules are not unique because any quantum scale device having cancellation of electric charge will show a similar effect if there is a temperature difference. With the increase in temperature difference, energy generated also increases.

Thermoelectric devices designed by Bergfield and Stafford can generate power that can light a 100 Watt bulb or increase car’s efficiency by 25%.

SEE COMMENT: Lets hope that the practical application of this effect can be brought to the development stage as soon as possible

Power (and Heat) generated from chicken litter after biogas plant opens in November 2010

Electrical Generation Side of Process

Cirencester in Gloucestershire is to become one of the first towns in the UK to benefit from power generated using chicken litter and other farming waste products. The Combined Heat and Power plant (CHP) which is due to open in November is being built on a farm to the south of the market town.

It will take animal waste as well as corn, wheat and grass from local farms and produce methane-rich biogas via a process of anaerobic digestion. This we believe is much more suitable than incineration.

The bio-gas will be used to power a Combined Heat and Power unit generating around 1MW of electricity, enough to supply 350 homes.

The wasted heat energy (around 2MW) will be used for keeping the animal sheds warm, drying grain and local housing central heating and hot water. The utilisation of this form of energy as usable heat is what makes this system so attractive. Every bit of energy, whether electrical or heat is used, unlike in traditional power stations where the heat is ejected to the atmosphere via those vast cooling towers.

After the biogas is extracted the fibrous material left is spread on the land as fertilizer. Now that' what we call efficiency.

At Sun Earth Energy this same technology can be used in a town near you!!! Please contact us for details. And by the way some of the wasted heat from this process can be used for air conditioning for commercial offices. This can be especially useful in the summer months when less heat load is needed.

Saturday, 24 July 2010

A combination of alternative energy and computational modelling developed by CSIRO in collaboration with Horticulture Australia Limited (HAL) and the Australian Prune Industry Association has cut energy requirements by 60 per cent in some areas of food processing.

This is how the ever rising need for energy can be halted and reversed. In most process industries (and in the home) there are always alternative ways of doing things. We are not talking about alternative energy we are talking alternative strategies. My pet favorite is air conditioning. The hotter the country the more need for air con - BUT, solar thermal assisted air con works really well in hotter locations. And it uses over 50% less electricity than 'traditional' air con systems.

But the Prune Industry Advisory Committee Chair Malcolm Taylor said reducing the cost of the dehydration process was of major interest."We were very interested in working with HAL and CSIRO to improve the cost efficiency of dehydration as it is a major proportion of total production costs," Mr Taylor said."Through this research, we expect companies will see major savings in energy, money and green house gas emissions as well as increases in throughput."

CSIRO’s Dr Henry Sabarez said that through experimental investigations at laboratory and commercial scale, assessment of operational practices pluscomputer modelling of dehydration tunnel design and performance, significant increases in energy efficiency and throughput had been made.

"In addition, further energy savings are likely with retrofitting of both heat recovery and solar-based heating systems in existing dehydrators," Dr Sabarez said.

"Working with the prune industry has shown the real bottom-line benefits that are possible from this approach. Other parts of the food processing industry, and indeed other processing industries, will also benefit."

Thursday, 22 July 2010

Solar-powered process could decrease carbon dioxide to pre-industrial levels in 10 years

July 22, 2010 By Lisa Zyga Phys Org

In the Solar Thermal Electrochemical Photo (STEP) carbon capture process, the sun’s visible light and heat are used to capture large amounts of carbon dioxide from the atmosphere and convert it to solid carbon for storage or carbon monoxide for fuel generation.

By using the sun's visible light and heat to power an electrolysis cell that captures and converts carbon dioxide from the air, a new technique could impressively clean the atmosphere and produce fuel feedstock at the same time. The key advantage of the new solar carbon capture process is that it simultaneously uses the solar visible and solar thermal components, whereas the latter is usually regarded as detrimental due to the degradation that heat causes to photovoltaic materials. However, the new method uses the sun’s heat to convert more solar energy into carbon than either photovoltaic or solar thermal processes alone.

The new process, called Solar Thermal Electrochemical Photo (STEP) carbon capture, was recently suggested theoretically by a team of scientists from George Washington University and Howard University, both in Washington, DC. Now, in a paper just published in The Journal of Physical Chemistry Letters, the scientists have experimentally demonstrated the STEP process for the first time.
“The significance of the study is twofold,” Stuart Licht, a chemistry professor at George Washington University, told PhysOrg.com. “Carbon dioxide, a non-reactive and normally difficult-to-remove compound, can be easily captured with solar energy using our new low-energy, lithium carbonate electrolysis STEP process, and with scale-up, sufficient resources exist for STEP to decrease carbon dioxide levels in the atmosphere to pre-industrial levels within 10 years.”

As the scientists explain, the process uses visible sunlight to power an electrolysis cell for splitting carbon dioxide, and also uses solar thermal energy to heat the cell in order to decrease the energy required for this conversion process. The electrolysis cell splits carbon dioxide into either solid carbon (when the reaction occurs at temperatures between 750°C and 850°C) or carbon monoxide (when the reaction occurs at temperatures above 950°C). These kinds of temperatures are much higher than those typically used for carbon-splitting electrolysis reactions (e.g., 25°C), but the advantage of reactions at higher temperatures is that they require less energy to power the reaction than at lower temperatures.

The STEP process is the first and only method that incorporates both visible and thermal energy from the sun for carbon capture. Radiation from the full solar spectrum - including heat - is not usually considered an advantage in solar technologies due to heat’s damage to photovoltaics. Even in the best solar cells, a large part of sunlight is discarded as intrinsically insufficient to drive solar cells as it is sub-bandgap, and so it is lost as waste heat.

By showing how to take advantage of both the sun’s heat and light for capturing and splitting carbon dioxide, the STEP process is fundamentally capable of converting more solar energy than either photovoltaic or solar thermal processes alone. The experiments in this study showed that the technique could capture carbon dioxide and convert it into carbon with a solar efficiency from 34% to 50%, depending on the thermal component. While carbon could be stored, the production of carbon monoxide could later be used to synthesize jet, kerosene, and diesel fuels, with the help of hydrogen generated by STEP water splitting.

“We are exploring the STEP generation of synthetic jet fuel and synthetic diesel,” Licht said, “and in addition to carbon capture, we are developing STEP processes to generate the staples predicted in our original theory, such as a variety of metals and bleach."

Tuesday, 6 July 2010

Researchers from TU Delft in the Netherlands have shown how the energy yield of relatively cheap solar panels, made of amorphous silicon, can be considerably raised: from around 7 percent to 9 percent.

Researcher Gijs van Elzakker focused onsolar panelsthat are made from so-called amorphous silicon, as opposed to the more commonly usedcrystalline silicon. Amorphous silicon has the great advantage that the solar panels can be produced relatively cheaply using a verythin layerof silicon (thin film solar cells).

The major disadvantage of solar panels made with amorphous silicon is that their yield is relatively low. While crystalline silicon achieves a yield of around 18 percent, amorphous silicon, until recently, remained at around 7 percent. This is partly because the amorphous silicon panels suffer from the so-called Staebler-Wronski effect. This phenomenon, which has still not been fully explained by science, manifests itself in the first hours that the panels are exposed tosunlight. Because of this the yield falls by around a third, from around 10 percent to around 7 percent.

In his doctoral research Gijs van Elzakker investigated adaptations in the production process that could raise the yield. The silicon layer in the solar panels he studied is made of silane gas (SiH4). The structure of the silicon layer can be changed by diluting this silane gas withhydrogenduring the production process. The use of hydrogen appears to enable the reduction of the negative Staebler-Wronski effect.

Van Elzakker concentrated, among other factors, on the proportion of hydrogen to silane gas. He determined the optimum ratio of hydrogen to silane in the production process. Van Elzakker: "We showed that the influence of the Staebler-Wronski effect can be considerably reduced in this way. If this knowledge is applied in the manufacture of this type of solar cells, a yield of 9 per cent can be expected."

Gijs van Elzakker's findings are already being applied on the production line of the German company Inventux Technologies, where he now works.

More information:Gijs van Elzakker will obtain his PhD on this subject from TU Delft on Tuesday 6 July.